Adding server's ip address to favorites so that I don't have to type it in all the time?

How do I make it so that I can add a favorite button that saves the ip address and lists it in the favorites list? Also so that I can connect to it. Please give me the most simplest ideas so that I can understand it since I am a beginner in multiplayer. Thanks.

EDIT: My game uses direct connecting features just like Minecraft

You can use PlayerPrefs to save information, such as an IP address.